Straight bar knitting machine



Filed Sept. 20, 1945 W. G. MACDONALD ET AL STRAIGHT BAR KNITTING MACHINE 6 Sheets-Sheet 1 W. G. MACDONALD ET AL 2,48%943 STRAIGHT BAR KNITTING MACHINE Filed Sept. 20, 1945 6 Sheets-Sheet 2 Z m yen 60m Q 00101 W F"- 6, W490 W. G. MACDONALD ET AL 243@9943 STRAIGHT BAR KNITTING MACHINE 5 W49 W. G. MACDONALD ET AL A STRAIGHT BAR KNITTING MACHINE Filed Sept. 20, 1945 6 Sheets-Sheet 4 wt 6 HWM W. e. MACDONALD ET AL 2,4@794i3 STRAIGHT BAR KNITTING MACHINE Filed Sept. 20, 1945 e Sheets-$heet 5 fiemfl 6 W490 W. G. MACDONALD ET AL WW STRAIGHT BAR KNITTING MACHINE Filed Sept. 20, 1945 6 Sheets-Sheet 6 Patented Sept. 6, 1949 STRAIGHT. BAR. KNITTING MACHINE William Gordon Macdonald and William Arthur Cooper, Loughborough, England, assignors. to William Cotton Limited, Loughborough, England Application September 20, 1945, Serial No. 617,594: In Great Britain August 2, 1944 8 Claims. 1

This invention concerns Cottons patent and other straight bar knitting machines, and primarily, those intended to. knit the blanks of ladies stockings. Such blanks have areas that are reinforced by knitting in an additional, or splicing or plating thread. The length of these areas is a substantial proportion of the total length of the blank, particularly in the case of blanks having aintegral foot, While their width is in certain places, such asthe high heel splicings, only a small proportion of the total length of the draw. In the art a distinction is made between the case in which the additional thread is plated on the main thread in these areas so as to appear constantly at one face of the fabric (as is necessary when, for example, the additional thread is cotton and the main thread is silk) and the case in which the relation of the two threads is immaterial or haphazard (as for example when both threads are of the same kind). In the first case the nomenclature plated splicing is used; in the second splicing. As is well known in the art it is necessary when knitting on a straight bar machine that the thread carrier shall have a lead over the slurcock .but when knitting plated splicing it is also necessary to ensure-that the plated splicing carrier shall have aconstant lead over the slurcock as well as that the main carrier shall have a. lead over the plated splicing carrier. The lead of the plated splicing carrier over the slurcock ismaintainedlas small as possible, to prevent the plated splicing thread from getting displaced and thus to ensure that the correct relative relationship of the ground and plating threads is maintained. Each plated splicing carrier rod is driven by two friction boxes on a friction bar, and considering for example the knitting of the left. high heel, of a stocking, one box drives the carrier inwards to the right from the selvedge to the inner-edge of thehigh heel area, and the other drives it inthe reverse direction to the left, up to the selvedge, the travel of the carrier being determined by adjustable carrier stops. Stops are also provided for the boxes; the left handone ends the traverse of, the first box to the left and the right hand one ends the traverse of the second box to the right. The setting of these friction box stops determines the lead of the plated splicing carrier over the slurcock. It will be appreciated however, that should one of the boxes slip slightly. on the rod when it should be driving the carrier, the correct lead of the carrier over the slurcock is lost, and since even the loss of one sinkerspace in lead is fatal to correct plating it is usual to have the friction boxes very tight. Evenso, difficulty is commonly experienced in plated splicing; moreover since during those parts of the draw wherein the-plated splicing carriers stand still their friction boxes slip, the heavy frictio throwsa considerable load 011 the riving motor of the machine; also, the heavy friction results in the impact of the carrier rod on its stops being excessive. Therefore, both because .of the difficulty in ensuring the constant plating leadand because. of said load and impact the machine speed is reduced during plated splicing. Ineifect, then, the plated splicing is an important factor in limiting the output of the machine.

Inthe case of splicing, since the relation of the threads is immateria'lthelead problem does not arise andeach splicing carrier rod is driven by a single friction box. Therefore, the frictional load isnot so severe although it still imposes limits on the machine speed.

An object of the present invention is the provision ofmechanismwhereby a carrier is given a constant lead over a 'sflurcock and whereby the frictional drag is reduced, and as, viewed from one aspect provides in a straight bar knitting machine having a frictional, device for driving the carrier frorna draw or 'Coulier. mechanism and stops or their equivalent for variably determining the length of. traverse of said carrier; means for disconhectingthe carrier from the frictiondevice. in the regionof theend of the carrier traverse and form-establishing the connection at. the commenccmsnt of the carrier traverse in the reverse direction. It will have been appreciated from .the foregoing discussion, however, the inventionis primarily applicable to the drive for a plated splicing carrier in a machine wherein the said carrier and the main carrier are driven by separate friction boxes; anobject being to ensure a constantlead over the slurcock for the platedsplicingcarrier while reducing the frictional drag, Therefore, asviewed from another aspeotgthelpresent invention provides a straight harknitting machine which has a single frictional device for driving a plated splicing carrier from a draw or Couiier mechanism, stops or their equivalent for variably determining the length oftraversepf saidoarrieli, andmeans for disconnecting said carrier, from. the friction device in the regiouoj-l the .endof the carrier traverse, and for re-establishing the. connection at the commencement of:thepar-rier traverse in the reverse direction. It; will therefore, Ice-appreciated that. the, frictiondevice -is. not required toslip ,undera heavy frictional loadthroughout the idle part of the draw, so that the load on the motor is reduced and the machine speed increased.

According to a subsidiary feature of the invention, stops are provided for determining the traverse of said frictional device. The setting of these stops is a factor in determining the lead of the frictional device over the slurcook.

The foregoing and other features of the invention set out in the appended claims are incorporated in the construction which will now be described with reference to the accompanying drawings as an example ofthe application to a Cottons patent knitting machine, itbeing only necessary to describe the mechanism for one plated splicing carrier since that for the other plated splicing carrier is similar.

In the accompanying drawings:

Figure 1 is an elevation looking from the rear of the machine (and to the left in Fi 2) showing relevant portions of the mechanism;

Figure 2 is a cross-section through'said mechanism;

Figure 3 is a plan, .on a smaller scale and to some extent diagrammatic, showing the arrangements of the mechanism at the left-hand end of the machine for the control of one platedsplicing carrier rod and Figure 4 is a like plan of the said mechanism at the right-hand end of the machine;

Figure 5 is a front elevation of the selvedge stops (located at the centre of the machine) for the two carrier rods and of the associated antirebound stops;

Figure 6 is an end elevation of said stops;

Figure 7 is a like front elevation of the graduating stop, located for the carrier to strike at the right-hand side to variably determine the inner'limit of travel of one rod to the right away from the selvedge, and of the associated antirebound stop, the corresponding graduatingstop for the other rod being similar and located for the carrier to strike at the left-hand side.

Considering the two plated splicing carrier rods la, lb shown in Fig. 3, the rod la is equipped with the usual carriers for plated splicing at the right hand margin of a stocking blank knitted on each of the divisions of needles A, B, C etc. and the rod lb is likewise equipped with carriers for plated splicing at the left hand margin. Rod la has its traverse to the right, and rod lb has its traverse to the left, determined for the purpose of stopping the carriers at the selvedges by the selvedge stop mechanism which is shown in Figs. 5 and 6 and which is located at the centre of the length of the machine. The traverse of rod la to the left, to bring the carriers to a standstill at the inner or left-hand edge of each plated spliced area (at the right hand margin of the blanks), is determined by the graduatin stop mechanism similar to that shown in Fig. '7 and located for the carrier to strike at the left-hand side. The graduating stop mechanism for determining the traverse of rod lb to the right hand is located for the carrier to strike at the right-hand side and is shown in Fig, 7. Each plated splicing carrier rod is driven by a mechanism such as is shown in Figs. 1 and 2; the particular mechanism illustrated is that for driving rod la and that for driving rod lb is identical.

The friction bar'2, which is moved to and fro by the draw mechanism, carries a friction box 3, while alongside the friction bar there is a stationary bar 4, carrying a sliding bracket 5 coupled by a finger 6 to the required plated splicing carrier rod (rod Ia in'FlgJ2) which bracket 5 carries a vertically slidable bolt 1, having a truck 8 at its bottom end and urged downwards by a spring 9. On the bolt 1 there is a projection l0 adapted to engage in a slot l I cut in a horizontal ledge l2 (having chamfered ends l2) on the face of the friction box 3. When the projection ll) is thus engaged, the bracket 5 is positively connected to the friction box 3. When the projection It] is lifted from the slot ll, the two are disengaged and the projection rides on the top of the ledge l2. The slot II is somewhat wider than the projection ll! so that the latter will not fail to enter.

Mechanism is provided for raising the bolt when the plated splicing carrier rod la strikes its selvedge stop or graduating stop. The slur or tie bar l3, which reciprocates with the friction bar 2, carries two spaced spring-loaded cams l la, l lb for operating on the truck 8. For example during travel of the slur bar, friction bar, and slurcocks from right to left of the machine (1. e. from left to right in the rear elevation shown in Fig. 1) the cam [4a rests against the tnuck 8 and assists in driving the carrier rod lb and its carriers. When the left hand stop (1. e. the graduating stop in this instance) is encountered, the carrier rod lb and bracket 5 are brought to a standstill but the cam I la carries on. It therefore raises the bolt 1 and disengages the projection Ill from the slot ll. During con tinued movement of the friction bar 2, box 3 and cams Ma, l lb to the right (and to the left in Figs. 3 and 4) the projection rests on the top of the ledge l2 which travels beneath it; the truck engages the cam Mb which is deflected downwards against a spring l5b and rises again when it has passed the truck. The friction box 3 is eventually brought to a standstill by an adjustable stop l6 which, for plated splicing, is inserted in front of the fixed member and during continued movement of the friction bar 2, tie bar I3, and slurcooks, the friction bar 2 slides through the box 3. The frictional load is very small however.

On the return traverse of the friction bar, the bar, and slurcocks to the right (to the left in Fig. 1) the friction box 3 picks up immediately. It will therefore be appreciated that the setting of stop I6 is a factor in determining the position of the friction box in relation to any given point on the friction 'bar and tie bar (e. g. in relation to the cams Ma, Mb) and in determining the lead. The projection l0 rides up the inclined end l2 on to ledge l2 (in the event of the preceding traverse of the carrier being sufliciently short for the projection to have travelled off the ledge) and eventually drops into the slot II, and at the moment when the drive is taken up by the wall (the right hand wall in Fig. 1) of the slot the cam Mb engages the truck and assists in the drive of the bracket and carrier. When the selvedge stop is reached, the cam Mb raises the bolt 1 and disconnects the drive in a manner similar to that just described, cam Ma being depressed by truck 8 against the return of spring I511. The travel of the friction box 3 is terminated by an adjustable stop l! (the setting of which is a factor in determining the lead, since during the short remaining travel of the friction bar 2 the latter slips through the friction box) A simple hand operated screw mechanism indicated generally at l8 in Fig. 1 is provided for adjusting the spacing between the two cams Ma, l4b by shifting their pivots along the tie bar 13 towards or away from one another.

It is desirable to provide anti-rebound stops rebounding from. the. selvedgerand graduating,

stops and to prevent them creeping; away from these stops. Dealing first. with;the. anti7rebound stops. which are. associated, with. the. selvedge t ps shown in Figs. ,5 and 6. for. terminating the travel ofthegrods la, I bltontharight. andleft rep ctively (said; selvedget stops. being. numbered 18a, i819; and;beingzadiustableby. screw [9 in known manner), each rod at its appropriate end carries 2. lug Informed with aslot 21 into which a bolt. 22.may descend under the influence of the spring 23. shown so that on. movemento f, thecarrier rod towards its selved'ge" stop "the lug '20' may readily force its way under the boltwhich then springs home. At the time at which the'carrir rod is required to travel-away from the selvedge stop it is necessary to release said bolt. For this purpose there is a vertical plungerit; having at its upper end an arm 25-underlyingarm 26 on the bolt 22; while at its lower' ehdtheplungei' M -car ries a truck 21 which is raised by cam 28 on the tie bar bracket. It is of course necessary to ensure that this cam 28 does not raise the plunger 2d and release the bolt 22 at the end of the traverse of the carrier rod but only at the commencement of the traverse, and for this purpose the cam 28 is formed with a ramp 28' which at the end of the said traverse displaces the truck 21 against the action of a spring 29 so that the cam passes the truck harmlessly.

A substantially similar arrangement is applied to each graduating stop, the graduating stop of the rod lb being illustrated at 30 in Fig. '7 as an' example of the two stops and being displaceable by screw 3! in known manner. The parts of the anti-rebound device associated with these graduated stops which correspond with the parts shown in Figs. 5 and 6 are given the same reference numbers but are distinguished by the reference character a; thus bolt 22a is the equivalent of bolt 22.

When plated splicing is not being carried out it is desirable to render the mechanism shown in Figs. 1 and 2 inoperative. This is effected by cams such as 32, 33, on the automatic shaft 34. Cam 32 operates by means of lever 35 to rock a rockshaft 36 carrying arms 31 supporting a horizontal bar 38 which engages under a pin 39 projecting from bolt 1 so that the bolt is raised to the inoperative position when required. Cam 33 rocks a lever 40 freely mounted on said rock-shaft 3B and carrying the stop l6 so that the latter is raised to the inoperative position as required.

In the foregoing mechanism the main carrier rod and its friction box are not described and illustrated since they are of conventional form.

It will be appreciated that the mechanism ensures that irrespective of the length of travel of a plated splicing carrier, each carrier has a constant lead over its slurcock this lead being determined by the setting of stops [6 and I1 and by the relative widths of slot I l and projection ll], Since the cams Ma, Mb assist positively in driving the carrier rod by virtue of their contact with truck 8, the friction of the friction box may be materially reduced. This reduction, combined with the fact that only one friction box is required for each plated splicing carrier rod (as contrasted with the two previously employed) in turn reduces the frictional load on the machine at such times as the box is held stationary by one or other of its stops. Furthermore, owing to the fact that the friction box is completely discon- This bolt has an inclined. face asnected from the carrier and the friction rod only slides through the frica.

tion box for the very short distance, that said; rod continues, totravel after the. box has. been;

brought to a standstill by stop l.6.a.or,.,l .1, the-.durae. tion of the frictional loadis materially reduced.

These factors tend to increase thespeed-at: which:

plated splicing maybe carriedout. toimprovethe. resultant fabric, to. reduce the. impact of; the;

carrier rod on itsstop, toimprovejthesmoOth running qualities ofthe machine, and :to decrease.

the power required to drive it.

We claim: 1. A straight 'bar knittingmachine, having; a.

single frictional. device for. driving a, platedz splicing carrier froma draw or.Coulier.mecha.-, nism, steps or their. equivalent for variablyedee.

termining the length of traverse of saidcarrier, and means for disconnecting saidcarrier. from the frictional device in the.regionofitheendiof; thecarrier. traverse and.for.re-establis"hing the;

connection at the commencement of the carrier traverse in the reverse direction.

2. A straight bar knitting machine comprising a carrier, a reciprocable draw member, a frictional device for driving the carrier from the draw member and comprising a first part travelling with the draw member and a second part for connection to the carrier, adjustable stop mechanism for variably determining the traverse of the carrier, stops for determining the traverse of said second part of the frictional device, a releasable coupling between said second part and said carrier, and means travelling with the draw member for releasing said coupling when the carrier travel in either direction is brought to a standstill by its stop mechanism and for re-connecting it during travel of the draw member in the reverse direction.

3. A machine, according to claim 2, wherein the coupling comprises a coupling member asso ciated with the carrier to engage with and disengage from the second part of the coupling, which member is movable by the release means travelling with the draw member.

4. A machine according to claim 1 having stops for determining the traverse of the frictional device.

5. In a straight bar knitting machine having a frictional device for driving a carrier from a draw or Coulier mechanism and means for variably determining the length of traverse of the carrier; means, additional to the frictional device, for assisting the latter in driving the carrier and also for disconnecting the carrier from the frictional device in the region of the end of the carrier traverse and for re-establishing the connection at the commencement of the carrier traverse in the reverse direction.

6. A machine according to claim 2 having means additional to the frictional device for assisting the latter in driving the carrier, and wherein said coupling comprises a coupling member associated with the carrier to engage with and disengage from the second part of the coupling, which member is movable by the release means travelling with the draw member.

'7. In a straight bar knitting machine having a frictional device for driving a carrier from a draw or Coulier mechanism, and stops for adjustably determining the traverse of the carrier; the combination of means for providing a drive, additional to that provided by the frictional device, for the carrier and for yielding and becomi rod. at the. moment} the; latter strikes its selvedge stopor graduating-step.

mg inoperative at each end of the carrier traverse, and mechanism for disconnecting the carrier from the frictional device at the end of each carrier traverse and for re-establishing the connection at the commencement of the next carrier traverse in the reverse direction.

8. In a straight bar knitting machine having a reciprocatable slur cock and a reciprocatable thread carrier, carrier-driving mechanism comprising two members reciprocating with the slur cook, a. friction box for driving the carrier from one of these members, adjustable stops for variably determining the traverse of the carrier, other adjustable stops for variably determining the travel of the friction box, a releasable coupling interposed between the friction box and comprising two coupling members whereof one is connected to the carrier and is movable into and out of engagement with the first one, and elements on the other reciprocating member spaced apart in the direction of reciprocation, one for operating on the movable coupling member during travel in one direction to assist in driving the carrier and for shifting the said coupling member at one end of the carrier traverse to an attitude in which said element may travel past said coupling member and in which the coupling is disengaged, and the second one for fulfilling like functions during travel in the opposite direction.

WILLIAM GORDON MACDONALD.

WILLIAM ARTHUR COOPER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date ,023,694 Walther Apr, 16, 1912 2,018,059 Friedmann Oct, 22, 1935 2,119,613 Verbeek June 7, 1938 2,158,498 Good May 16, 1939 2,161,550 ,Mutchler June 6, 1939 2,195,578 Meinig et a1. Apr. 2, 1940 

